4.5.1 Protocol : AEG SEAB-1F, Modnet-1/F, U250


 

Telegram structure

Each telegram consists of single UART characters, with 1 start bit, 8 bit information, 1 parity bit and 1 stop bit. The transmission of data bytes takes place after the principle "LSB first".It is an asynchronous protocol protocol with the hamming distance = 4. Via the parity bit in the asynchronous character each byte is secured with d = 2. The telegram is additionally secured with a security byte, in which a hamming distance of d = 4 is reached. The security byte is done by completion to an odd number of "1" over all telegram bytes.

 

Information about the structure of the telegram see
<AEG SEAB-1F : Telegram structure>

 


AEG SEAB-1F : Configuration

 

 

With the channel button ( channel 1 ...12 ) on the bottom following settings are possible :

 

Each character has one start bit ( binary = 0 ), 8 information bits and normally one odd parity bit and one stop bit ( binary = 1 ).

 

Interface

For each channel any COM port ( COM 1 till COM 24 ) can be selected.

Modem

An individual modem can be installed and connected for each channel. LIAN 98 is able to process up to twelve modems in the range of COM1 till COM24 simultaneously. Select here the modem assigned to the selected channel. Normally this assignment will be recognized by LIAN 98 and the corresponding modem will be set.

Setup Modem

The settings of the modem must be executed via the windows control panel "telephone and modem options". With this button you can check the modem settings and see if they correspond to the LIAN 98 configuration.

Connection type

Attention, the connection type should be set to full duplex for monitoring !
 

Full duplex :

Most of the modems are full duplex and can transmit data in both directions simultaneously. DTE ( LIAN 98 ) and DCE ( Modem ) work simultaneously as transmitter and receiver. None of both transmitters has to wait for clearance for transmitting data. Therefore the signals RTS and CTS are not significant. Sure, LIAN 98 is setting the control signals RTS and DTR to 1 when it is ready for transmission and receipt but it does not check the signals CTS and DSR.

Half duplex :

In case of a half duplex connection DTE ( LIAN 98 ) as well as DCE ( Modem ) can work as transmitter and receiver, hereby only one data line ( 2-wire connection ) is available that can be used alternately for transmission or receipt of data. The control signals RTS and CTS are used in order to define the allocation of transmission or receipt. When LIAN 98 should work as transmitter it activates the signal RTS and waits for the confirmation of the modem via the signal CTS. After the receipt of the signal CTS the data are transmitted and after the transmission of the data the signal RTS is set to 0. In each other case LIAN 98 is working as receiver only.

As long as the LIAN 98 software is ready for transmission and receipt the signal DTR is activated in order to show the modem that LIAN 98 is ready for operation, as well the software expects an activated DSR signal from the modem.

RTS Leading delay

0 ... 1000 msec
This parameter ist only used for the connection type "half duplex" and is determined by the initial transient behaviour of the used transmission equipment.
The RTS Leading defines the delay time from activating RTS signal to transmitting the first character and is used for modems whithout the hardware handshake signals "RTS and CTS". In this case the "RTS signal" must be led back over the "CTS line" to the PC with the help of a brazing bridge in the monitor cable. Dependent of the used modem it may be necessary to connect additionally the DTR-pin with the DSR-pin.
This function is deactivated if the "Leading and the Trailing" is set to NULL and therefore the control signals are analyzed diectly from the modem.

RTS Trailing delay

0 ... 1000 msec
This parameter ist only used for the connection type "half duplex" and is determined by the final transient behaviour of the used transmission equipment.
The RTS Trailing defines the delay time from the last character transmitted up to the RTS signal is deactivated.
This function is deactivated, if the "Leading and the Trailing" is set to NULL.

 

Baud rate

Transmission speed : 25 - 115200 baud ( variable )

Data byte

8 bit ( fixed )

Stop bit

1 bit ( variable )

Parity

odd ( variable )

Time out

1 - 9999 msec ( variable )

 

Transmission procedure
B :
balanced,
Point-to-Point

If balanced transmission procedure is used, each station may initiate message transfers. The balanced mode is restricted to "point-to-point" or "multiple point-to-point". Balanced mode can be used in a full duplex transmission.

U :
unbalanced,
Party line

Unbalanced transmission is used in SCADA systems in which a master station controls the data traffic by polling outstations sequentially. The master station is the primary station that initiates all message transfers while outstations are secondary stations ( slaves ) that may transmit only when they are polled.
The unbalanced mode can be used generally, but must be used in party line configuration.

 


AEG SEAB-1F : Simulation

 

AEG SEAB-1F : RTI ( Master )-Simulation

In the polling mode ( unbalanced ) LIAN 98 simulates a MASTER and can communicate with up to 32 connected substations simultaneously.

 

Station address
( address of the target station )

All telegrams to be sent are provided with the link address of the SIM list during master simulation.

Exception for unbalanced mode :
. If the station address 127 for a broadcast command is inserted in a telegram in the TDB buffer, the telegram will be transmitted unchanged with the address already inserted.
. If a station address out of the Scan list is inserted in a telegram, the telegram will be transmitted unchanged with the address already inserted.

Response timeout

1 - 30 000 msec

The SEAB-1F protocol specifies a fixed time out interval to be used for repeated frame transmissions. The time out interval and maximum number of retries are configurable and appropriate values will depend on the transmission system.

This parameter determines the time in milliseconds that the program LIAN 98 as primary station at most has to wait for an acknowledge before the last transmission is repeated.

Number of frame retries

0 - 255

Via this parameter it is defined how many times the transmission is to be repeated when the acknowledge is missing.

Enable clock synchronization

yes / no

After the initialization of the communication LIAN 98 will transmit first of all a time synchronization command and will repeat it cyclic ( Clock SYNC cycle time ), if this parameter is activated.

Use system date/ time

yes / no

If this parameter is activated the system time of the PC will be taken over as time stamp before transmitting the telegrams. Otherwise the telegram remains unchanged as before edited by the user.

Clock SYNC cycle time

1 - 1440 minutes

Dependent on this time LIAN 98 as master station will transmit the time synchronization command continually.

Set time ( TDBnum )

Number of the TDB buffer in which the organization command ( 2FH ) "Set time" is stored.

Send date set command

yes / no

If this parameter is activated LIAN 98 first of all will once send a date set command after the initialization of the connection.

Set date ( TDBnum )

Number of the TDB buffer in which the organization command ( 2FH ) "Set date" is stored.

Enable general interrogation

yes / no

After the initialization of the communication LIAN 98 will transmit a general interrogation command and will repeat it cyclic ( GI cycle time ) when necessary, if this parameter is activated.

GI cycle time

1 - 1440 minutes

Dependent on this time LIAN 98 as master station will transmit the general interrogation command continually.

GI command

Number of the TDB buffer in which the organization command ( 2FH ) "General interrogation" is stored.

Send quittance

yes / no

LIAN 98 will send an acknowledge after the receipt of a telegram if this parameter is activated. The acknowledge is also a short request to the same station.

Quittance ( TDBnum )

Number of the TDB buffer in which the single character "Quittance" ( short request ) is stored.

Insert scan addresses
Number of addresses
delete
insert

Unbalanced : ( Party line / Line operation )
All stations to be processed at this line have to be inserted into the scan list. LIAN 98 establishes the connection to all this stations ( max. 32 stations ) and interrogates continuously the process data of this stations.

In order to insert the addresses please proceed as follows :

Activate "Insert scan addresses" ( button "insert" will be displayed ).
Insert in the fields "Link address" / "Address of ASDU" the station to be entered in the scan list.
Take over the addresses into the scan list by clicking "insert".
When all stations are inserted, please deactivate "insert scan addresses" ( button "insert" disappears ).

In order to delete a station out of this list select it and click "delete".

Deactivate polling cycle

Unbalanced : yes / no

When the connection with the substation is finished LIAN 98 starts automatically with the interrogation of the stations. If this is not wanted, the polling can be deactivated here.

Short request

Unbalanced :
Number of the TDB buffer in which the telegram "Short request" is stored.

Request delay

Unbalanced : 0 - 30 000 msec

This parameter determines the time that the program LIAN 98 delays the next short request.

 

AEG SEAB-1F : RTU ( Slave )-Simulation

 

 

Station address

All telegrams to be sent will be provided with the link address out of the SIM list during slave simulation.

Response timeout

balanced : 1 - 30 000 msec

The protocol SEAB-1F specifies a fixed time out interval to be used for repeated frame transmissions. The time out interval and the maximum number of retries are configurable and appropriate values are depend on the transmission system.

This parameter determines the time in milliseconds that the program LIAN 98 as primary station ( only balanced ) at most has to wait for an acknowledge before the last transmission is repeated.

Number of frame retries

Balanced : 0 - 255

Via this parameter it is defined how many times the transmission is to be repeated when the acknowledge is missing ( only balanced ).

Enable clock synchronization

yes / no

The current system time of the PC is given back in the "activation confirmation" of the time synchronization command, if this parameter is activated. Otherwise the received time will only be mirrored.

Set new system date/ time

yes / no

With the receipt of the organization command "set time " also the system time of the PC is updated with the new values if this parameter is activated.

Time correction
( system time of the PC )

0 - 9 999 msec ( Telegram run time correction )

A correction value can be entered for the setting of the PC system time with a time synchronization command. It will be added onto the received value in the synchronization command.

Use PC time

yes / no

The system time of the PC will be inserted as time stamp in the telegram before transmission. Otherwise the telegram remains unchanged as before edited by the user.

Send quittance

yes / no

LIAN 98 as substation will send a quittance after the receipt of a telegram of the master if this parameter is activated.

Quittance ( TDBnum )

Number of the TDB buffer in which the single character "Quittance" is stored.

 


 

AEG SEAB-1F : Simulation procedure

 

Simulation of the communication services :

The parameter [response timeout] determines the time in milliseconds that LIAN 98 after transmitting a primary message at most has to wait for an acknowledge before the transmission is repeated or a new message is sent. Via the parameter [number of frame retries] it is defined how many times the message has to be repeated. As long as the program LIAN 98 is waiting for an acknowledge no further telegram is sent. Send records are put down in the send list temporarily and will be sent after the receipt of the acknowledge.

 

Data acquisition by cyclic polling
( unbalanced )

Data acquisition is used in unbalanced data transmission procedures to update the controlling station with actual states in the controlled stations. The controlling station performs polling by interrogating the controlled stations sequentially. Controlled stations may only transmit when they are polled.

Cyclic polling is done automatically by LIAN 98 when master (RTI) simulation is started and the transmission procedure in the configuration is set to "U = unbalanced" and is not deactivated over the SIM list.

 

Simulation of the application functions :

 

Cyclic data transmission

Cyclic data transmission is used to provide a continuous updating function of current values of process variables in balanced and unbalanced transmission procedures.

A cyclic data transmission is done in LIAN 98 via sending cyclic send jobs ( see "transmit" ) or a not terminated send sequence ( see "send sequence list" ).

 


AEG SEAB-1F : Pre-filter/ Pre-trigger

 

AEG SEAB-1F : Monitoring filters

 

Monitoring filters reduce capture on particular pre-defined data records. By setting the corresponding filters a carefully directed data preselection can be achieved, which results in a reduction of the data to be analyzed later.

 

 

Filter released

yes / no

With this option already set monitoring filters for one channel can be deactivated temporarily without deleting them.

protocol specific
filter mask

Here monitoring can be filtered for telegram specific values in which several OR-linked filter masks can be defined for the channel.

= Only values equal to 'from' are let through.
# Only values not equal to 'from' are let through.
< Only values less than 'from' are let through.
> Only values greater than 'from' are let through.
R 'from' and 'till' define a valid range
add Adds the next OR-element.
remove Removes the current OR-element.

 

AEG SEAB-1F : Action filters

 

For the simulation and execution of data tests actions can be caused with the receipt of defined records. Therefore the possibility exists to define action filters, that effect the transmission of a send-sequence or transmit one or more message buffers ( TDB ).

 

 

Action filter released

yes / no

With this option already set action filters for one channel can be deactivated temporarily without deleting them.

protocol specific
filter mask

The action filter is described over telegram specific features corresponding to a filter setting. Additionally each action filter requires an allocation to a send buffer or alternatively to a send sequence.

= Only values equal to 'from' are let through.
# Only values not equal to 'from' are let through.
< Only values less than 'from' are let through.
> Only values greater than 'from' are let through.
R 'from' and 'till' define a valid range
Sendbuffer number
( from, from/ till )

In correspondence with the action filter the message buffer "from" or the message buffers "from/ till" are to be sent.

Sequence line number
( from, from/ till )

In correspondence with the action filter the send sequence is to be started at line number "from" or to be started at line number "from" and to be ended at line number "till".

add Adds the next OR-element.
remove Removes the current OR-element.

 

AEG SEAB-1F : Start trigger

 

With the receipt of a telegram pre-defined as start trigger, recording is started.

 

 

Start trigger released

yes / no

With this option already set start triggers for one channel can be deactivated temporarily without deleting them.

protocol specific
trigger mask

Here you can define telegram specific start triggers for monitoring in which several OR-linked triggers can be defined for the channel.

= Only values equal to 'from' are let through.
# Only values not equal to 'from' are let through.
< Only values less than 'from' are let through.
> Only values greater than 'from' are let through.
R 'from' and 'till' define a valid range
add Adds the next OR-element.
remove Removes the current OR-element.

 

AEG SEAB-1F : Stop trigger

 

Monitoring can also be stopped by telegram-specific filters and/ or "stop on error" after a defined number of following records. The number of the following records is defined in the field "records after stop on error/ stop trigger" in the global parameters of the VFL settings.

 

 

Stop trigger released

yes / no

With this option already set stop triggers for one channel can be deactivated temporarily without deleting them.

protocol specific
trigger mask

Here you can define telegram specific stop triggers for monitoring in which several OR-linked triggers can be defined for the channel.

= Only values equal to 'from' are let through.
# Only values not equal to 'from' are let through.
< Only values less than 'from' are let through.
> Only values greater than 'from' are let through.
R 'from' and 'till' define a valid range
add Adds the next OR-element.
remove Removes the current OR-element.

 


Each alteration in the settings is displayed by an asterisk * in the caption title and will be only effective after saving.

 


AEG SEAB-1F : Message display format

 

The sent and received messages of all channels are entered binary into the archive file. Before displaying on screen, the binary archived data are coverted to an easily readable procedure specific plaintext. In order to optimize the representation it can be chosen between three different plaintext settings. The plaintext format is set separately for each channel.
( see also "FMT file - Display format" )

 

 

Plaintext format 1

Everything is displayed : Telegram header and information elements

Plaintext format 2, 3

No header is displayed : Only information element is displayed

Plaintext format 4, 5

No information element is displayed : Only telegram header is displayed

 

Additional to the plaintext output the transmission data can also be displayed in hexadecimal, decimal, ASCII, binary ( LSB first ) or binary ( MSB first ). Of course the plain text output can also be deactivated in order to display the transmission data only e.g. hexadecimal.

 


AEG SEAB-1F : Error messages

 

Error checks during receive

 

per character

the start bit, the stop bit and the parity.

per frame

the checksum and the length.

 

*** TimeOut !

Within a telegram, there may be no pause between characters. In case of timeout occurs it is assumed that it is the end of the telegram and the telegram check is started. The sensitivity can be parameterized in the configuration ( timeout ).
Normally a time out is no error, but it is stored in the Pro file together with the initial error for a better analysis of the faulty transmission line in connection with a line error.

*E: COM-PORT !

Error during writing on the COM port. May be it is already occupied by another program.

E: Length !

The length of the telegram is wrong.

*E: Checksum !

The telegram checksum in the checksum byte is incorrect.

*E: Overflow !

Error message from the UART. This error is noted only in the PRO file.

*E: Parity !

Error message from the UART. This error is noted only in the PRO file.

*E: Start/ Stop !

Error message from the UART. This error is noted only in the PRO file.

 

Error checks during simulation

 

*E: DIR bit !

Direction bit is set wrong.

*E: unexpected !

The respond at this time was not expected.

*E: Link address !

The received station address is incorrect or the entry in the SIM list is wrong.

 


AEG SEAB-1F : Parameter list

 

The parameter list is not used for the protocol AEG SEAB-1F.

 


MAYR Software

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Manual LIAN 98


LIAN 98 Protocol Router, Simulator and Analyzer
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